Transferring Application State Across Devices

ABSTRACT

A first client device or system performs a method that includes retaining in memory registration information for a respective application indicating the respective application is registered for sharing application state with other client devices or systems. The method further includes storing an application state of a respective application, and detecting a transfer triggering condition. The transfer triggering condition includes presence of a second client device or system within a predefined proximity of the first client device or system, and the predefined proximity is a predefined proximity for near field communication. Furthermore, upon detecting the triggering condition, the first client device or system determines, in accordance with the stored registration information, that the respective application is registered for application state sharing, and transmits the application state of the respective application to the second client device or system.

RELATED APPLICATIONS

This application is a continuation of U.S. patent application Ser. No.13/247,755, filed Sep. 28, 2011, now U.S. Pat. No. 8,171,137, and alsoclaims priority to U.S. Provisional Patent Application No. 61/484,187,filed May 9, 2011, entitled “Transferring Application State AcrossDevices,” each of which are incorporated by reference herein in theirentireties.

TECHNICAL FIELD

The disclosed embodiments relate generally to wireless communication andmore particularly to transferring use of one or more applicationsbetween two devices through wireless communication connections.

BACKGROUND

A user with multiple devices, such as one or more smart phones, tablets,laptop computers or the like, may want to switch from using one deviceto another while continuing to work with or access the same applicationor content. For example, the user may want to transfer from one deviceto another in order to use the device best suited for a given task. Forexample, it is easy to read email from a smart phone but difficult toreply due to the size limitations on the phone keyboard. A user maystart a draft of a message on a phone, but prefer to finish the draftusing a tablet, which has a larger keyboard. In another example, a userstarts playback of a video using a tablet or smart phone, but wouldprefer to continuing viewing the video on a device with a larger screensuch as a television or laptop computer. In yet another example, a usermay start a phone call using a landline telephone but want to continuethe phone call using a mobile phone using a cellular connection, or viceversa.

SUMMARY

In some embodiments, a first client device or system performs a methodthat includes retaining in memory registration information for arespective application indicating the respective application isregistered for sharing application state with other client devices orsystems. The method further includes storing an application state of arespective application, and detecting a transfer triggering condition.The transfer triggering condition includes presence of a second clientdevice or system within a predefined proximity of the first clientdevice or system, and the predefined proximity is a predefined proximityfor near field communication. Furthermore, upon detecting the triggeringcondition, the first client device or system determines, in accordancewith the stored registration information, that the respectiveapplication is registered for application state sharing, and transmitsthe application state of the respective application to the second clientdevice or system.

In some embodiments, a non-transitory computer readable storage mediumstores one or more programs for execution by one or more processors of aclient device or system, the one or more programs comprisinginstructions that, when executed by the one or more processors, causethe first client device or system to perform the above described method.

In some embodiments, a distributed system comprising a first clientdevice or system under control of a respective user and a second clientdevice or system perform a method that includes the first client deviceor system executing first application. The method further includes thefirst client device or system performing a handoff operation thatcomprises transmitting application information, associated with thefirst application, to the second device or system when the first clientdevice or system is positioned within a predefined proximity of thesecond client device or system. The first application has a first clientdevice user interface state when the handoff operation is performed. Inresponse to receiving the application information from the first clientdevice or system, the second client device or system executes a secondapplication corresponding to the first application with an initial userinterface state corresponding to the first client device user interfacestate.

In some embodiments, a distributed system comprising a first clientdevice or system under control of a respective user and a second clientdevice or system perform a method that includes the first client deviceor system executing first application. The method further includes thefirst client device or system performing a handoff operation thatcomprises transmitting application information, associated with thefirst application, to the second device or system when the first clientdevice or system is positioned within a predefined proximity of thesecond client device or system. The first application has a first clientdevice user interface state when the handoff operation is performed.Furthermore, the first client device or system receives from anotherclient device or system application information associated with a thirdapplication, and in response, executes a second applicationcorresponding to the third application with an initial user interfacestate corresponding to a user interface state of the other client deviceor system.

In some embodiments, a non-transitory computer readable storage mediumstores one or more programs for execution by one or more processors of aclient device or system, the one or more programs comprisinginstructions that, when executed by the one or more processors, causethe client device or system to perform the above described method.

Furthermore, in some embodiments, a plurality of client devices storethe same one or more programs, or operationally equivalent programs, andare configured to either transmit application information, or receiveapplication information, in a respective handoff operation.

BRIEF DESCRIPTION OF THE DRAWINGS

For a better understanding of the disclosed embodiments, referenceshould be made to the Description of Embodiments below, in conjunctionwith the following drawings in which like reference numerals refer tocorresponding parts throughout the figures.

FIG. 1 is a block diagram of a system for enabling transferringapplication state across devices according to one embodiment.

FIG. 2 is a block diagram illustrating of a client device or system, inaccordance with some embodiments.

FIGS. 3A-3C include a flow chart illustrating a method of operation of aclient device or system, for transmitting the application state of arespective application to another client device or system, in accordancewith some embodiments.

FIGS. 4A-4C include a flow chart illustrating a method of facilitatingtransitioning use of an application by a user from a first client deviceor system to a second device or system, in accordance with someembodiments.

FIGS. 5A-5C include a flow chart illustrating a method of transmittingthe application states of a plurality of actively running applicationsfrom a first client device or system to a second client device orsystem, in accordance with some embodiments.

FIG. 6 includes a flow chart illustrating a method of transmitting theapplication state of an actively running application from a first clientdevice or system to a second client device or system, in accordance withsome embodiments.

DESCRIPTION OF EMBODIMENTS

It will be understood that, although the terms “first,” “second,” etc.may be used herein to describe various elements, these elements shouldnot be limited by these terms. These terms are only used to distinguishone element from another. For example, a first application could betermed a second application, and, similarly, a second application couldbe termed a first application, without changing the meaning of thedescription, so long as all occurrences of the “first application” arerenamed consistently and all occurrences of the second application arerenamed consistently. The first application and the second applicationare both application, but they are not the same application.

The terminology used herein is for the purpose of describing particularembodiments only and is not intended to be limiting of the claims. Asused in the description of the embodiments and the appended claims, thesingular forms “a”, “an” and “the” are intended to include the pluralforms as well, unless the context clearly indicates otherwise. It willalso be understood that the term “and/or” as used herein refers to andencompasses any and all possible combinations of one or more of theassociated listed items. It will be further understood that the terms“comprises” and/or “comprising,” when used in this specification,specify the presence of stated features, integers, steps, operations,elements, and/or components, but do not preclude the presence oraddition of one or more other features, integers, steps, operations,elements, components, and/or groups thereof.

As used herein, the term “if” may be construed to mean “when” or “upon”or “in response to determining” or “in accordance with a determination”or “in response to detecting,” that a stated condition precedent istrue, depending on the context. Similarly, the phrase “if it isdetermined [that a stated condition precedent is true]” or “if [a statedcondition precedent is true]” or “when [a stated condition precedent istrue]” may be construed to mean “upon determining” or “in response todetermining” or “in accordance with a determination” or “upon detecting”or “in response to detecting” that the stated condition precedent istrue, depending on the context.

Reference will now be made in detail to various embodiments, examples ofwhich are illustrated in the accompanying drawings. In the followingdetailed description, numerous specific details are set forth in orderto provide a thorough understanding of the described embodiments.However, some embodiments may be practiced without these specificdetails. In other instances, well-known methods, procedures, components,and circuits have not been described in detail so as not tounnecessarily obscure aspects of the embodiments.

FIG. 1 is a block diagram illustrating a distributed system 100 havingtwo or more client devices or systems 102 (hereinafter called clients102). The distributed system 100 typically further includes one or morecommunication networks 120 and a plurality of application servers orserver systems such as one or more messaging servers 130 and one or moremultimedia servers 140.

In some embodiments, each of the clients 102-1 and 102-2 has a nearfield communication (NFC) module 104 for handling NFC communications, anetwork module 106 for handling network communications, an applicationtransfer module 108 discussed in more detail below, and one or moreapplication programs 110, 112, 114. NFC modules 104-1 and 104-2 enableNFC communication between NFC-enabled devices. In some embodiments, theapplications on a client 102 include one or more messaging applications110, one or more multimedia applications 112 and optionally otherapplications 114 as well. As described in more detail below, in someimplementations, when a user brings two clients 102 into close proximity(e.g., within NFC communication distance of each other, which typicallymeans within 10 cm of each other, but optionally means within 5 cm or 4cm), the application state of one or more applications (e.g., the activeor foreground application) on one of the clients (e.g., client 102-1) istransferred to the other client (e.g., client 102-2).

Messaging server 130 includes one or more messaging server applications131, a messaging database 133 that stores messaging account information135 for multiple users of a messaging service supported by server 130,and optionally other databases 137 as well. For example, messagingserver 130 may be a Gmail server, an email server other than a Gmailserver, or an instant messaging server. Multimedia server 140 includesone or more multimedia server applications 141, one or more multimediadatabases 143, including multimedia account information 145, andoptionally other databases 147 as well. Examples of multimedia server140 include a YouTube server, online radio servers, and social gamingservers.

In some implements, a user reading an email message using a client-sidemessaging application 110-1 (e.g., Gmail) on his mobile cell phone(client 102-1) may instead want to reply to the message on a nearbydesktop computer (client 102-2) that has a larger keyboard and a biggerdisplay screen. To do this, the user brings his mobile cell phone 102-1into close proximity with computer 102-2. Both clients 102 have NFCmodules 104. NFC module 104-1 in client 102-1 detects the presence ofcomputer 104-2, and a NFC communication connection is establishedbetween mobile phone 102-1 and computer 102-2. The current state ofmessaging application 110-1, in this example comprising the user'saccount identifier (e.g., username@domainname.com) and messageidentifier is transmitted over the NFC connection to computer 102-2.Optionally, messaging application 110-1 in client 102-1 alsocommunicates with messaging server 130 over communications networks 120to ensure that server 130 has the most recent status with respect to themessage currently displayed by client 102-1. Computer 102-2 receives thecurrent state of messaging application 102-1 from the phone 102-1, andin response, messaging application 110-2 in computer 102-2 downloads acopy of the email message from messaging server 130 via communicationnetworks 120. From the user's point of view, as soon as he sits down infront of the display of computer 102-2, the same email message he wasreading on phone 102-1 is now displayed on the display screen ofcomputer 102-2 and he can start typing his reply using the keyboard ofcomputer 102-2.

FIG. 2 is a block diagram illustrating a client device or system(client) 102 in accordance with some embodiments. Client 102 typicallyincludes one or more processors 202 (also called processing units orCPU(s)), memory 204, a near field communication (NFC) transceiver(transmitter and receiver) 206, one or more network or othercommunication interfaces 208, a user interface 205 (typically includingcomprising a display device and a keyboard, mouse, touchpad, touchscreenor other input device), and one or more communication buses 209 forinterconnecting these components. The communication buses 209 optionallyinclude circuitry (sometimes called a chipset) that interconnects andcontrols communications between system components. Memory 204 typicallyincludes high-speed random access memory, such as DRAM, SRAM, DDR RAM orother random access solid state memory devices; and optionally includesnon-volatile memory, such as one or more magnetic disk storage devices,optical disk storage devices, flash memory devices, or othernon-volatile solid state storage devices. Memory 204 optionally includesone or more storage devices remotely located from the CPU(s) 202. Memory204, or alternatively the non-volatile memory device(s) within memory203, comprises a non-transitory computer readable storage medium. Insome embodiments, memory 204 or alternatively the non-transitorycomputer readable storage medium stores the following programs and/ormodules for execution by the one or more processors 202 and datastructures, or a subset thereof:

-   -   an Operating System 210 that includes procedures for handling        various basic system services and for performing hardware        dependent tasks;    -   a network communications module (or instructions) 106 that is        used for connecting client 102 to other computers (e.g.,        messaging server 130 or multimedia server 140) via one or more        network interfaces 208 (wired or wireless) and one or more        communication networks 120 (FIG. 1), such as the Internet, other        wide area networks, local area networks, metropolitan area        networks, and so on;    -   a near field communications module 104 for connecting client 102        to other clients, devices or systems via NFC transceiver 206,        using near field communications;    -   an application registration module 212, which maintains        application registration information 214 for one or more        applications that are registered for sharing their application        state with other client devices or systems information; for        example, application registration information 214 may include        information for a messaging application 110 that is registered        to share its application state with another device (e.g., client        102-2) upon detection of a triggering condition;    -   an application transfer module 108, for transferring the        application state of one or more applications (e.g.,        applications registered with application registration module 212        to share application state) to another device (e.g., client        102-2) upon detection of a triggering condition; and    -   one or more applications 110, 112, 114, such as a messaging        application 1120, browser or multimedia application 112, and        optionally one or more other applications 114.

In some implementations, near field communications module 104 includesan NFC detection module 220 and an NFC communication module 222. NFCdetection module 220 detects the presence of another NFC-enabled deviceor system within a predefined proximity and notifies client 102 upondetecting the presence of another NFC-enabled device or system withinthe predefined proximity. The predefined proximity is typically theproximity required to successfully establish an NFC communicationchannel (also called an NFC connection) between two devices, or tosuccessfully conduct NFC communications. While environmental conditionscan affect the ability to form an NFC connection, the predefinedproximity is typically no greater than 10 cm, and in someimplementations requires the two devices to be within 5 cm or 4 cm ofeach other. NFC communication module 222 handles communications betweenclient 102 and other device via NFC transceiver 206, such as thetransmission or receipt of application state, or application stateinformation, for one or more applications.

In some implementations, application registration information 214includes, for each registered application one or more of: an applicationprogram identifier, a mime type, and information (e.g., a procedurename, reference to an API, or the like) that enables applicationtransfer application to obtain the application state of the registeredapplication. Optionally, application registration information 214 ismaintained by client 102 as a searchable database, table or list.

In some implementations, a respective application program stores its ownapplication state information during execution, and thus the applicationstate is updated from time to time. Depending on the type of theapplications running, the information type and the size of theapplication state (e.g., the amount of memory required to store theapplication state) may be different from one application to another, andmay be stored either locally (i.e., on client 102) or remotely, such ason a remotely located server.

In some embodiments, messaging application 110 locally stores messagingapplication state information 224, as well as a user identifier oraccount name 226. The user identifier or account name 226 indicates theuser or account for which messages or other information is beingdisplayed by messaging application 110. Depending on the currentapplication context of messaging application 110, messaging applicationstate information 224 includes at least one of: the identifier of amessage and the format of the message currently viewed or worked on bythe user, information identifying a list of messages currently displayedby client 102, information identifying a list of conversations(sometimes called message threads) currently displayed by client 102,information identifying a contact for which contract information iscurrently displayed by client, etc. Messaging application stateinformation 248 may be saved either locally at client 102, or remotelyon a messaging server.

In some embodiments, browser or multimedia application 112 locallystores browser application state information 228. In someimplementations, browser application state information 228 is orincludes the URL of a document currently being viewed, and is savedlocally at client 102. Optionally, browser application state information228 is or includes additional information, such as one or more of:document position, playback position, user entered content ormodifications to the displayed document, etc.

Optionally, other applications 114, if provided, store application stateinformation 230 of various types, depending on the type of application.

Each of the above-identified modules, applications or programscorresponds to a set of instructions, executable by the one or moreprocessors of client 102, for performing a function described above. Theabove identified modules, applications or programs (i.e., sets ofinstructions) need not be implemented as separate software programs,procedures or modules, and thus various subsets of these modules may becombined or otherwise re-arranged in various embodiments. In someembodiments, memory 203 optionally stores a subset of the modules anddata structures identified above. Furthermore, memory 203 may storesadditional modules and data structures not described above.

FIGS. 3A-3C include a flow chart illustrating a method 300 of operationof a client device or system (hereinafter called a client, for ease forreference) according to some embodiments. Method 300 is performed by afirst client, such as client 102-1 described above with reference toFIGS. 1 and 2. Registration information (e.g., 214, FIG. 2) for arespective application (e.g., messaging application 110,browser/multimedia application 112) indicating that the respectiveapplication is registered for sharing application state (e.g., messagingapplication state 224 or browser application state 228) with otherdevices is retained in memory (302). The application state of therespective application is stored either in memory of client 102 or inmemory of a server at a remote location from the client (304). Duringexecution of the respective application, the application state isdynamically updated and stored in memory, as needed.

A transfer triggering condition for transferring application state ofthe respective application to another device client (e.g., from firstclient 102-1 to second client 102-2, FIG. 1) is detected (306). Thetriggering condition is presence of another device (e.g., second client102-2) within a predefined proximity of first client 102-1 (308). Thisis sometimes herein called a “zero-click” triggering condition, for“zero-click” sharing. As noted above, the predefined proximity istypically the proximity required to successfully establish an NFCcommunication channel (also called an NFC connection) between twodevices, or to successfully conduct NFC communications. In variousimplementations, the predefined proximity is no greater than 10centimeters, 5 centimeters, or 4 centimeters. In some implementations,in addition to detecting the NFC field of another device, a “bump” mustbe detected (e.g., using one or more accelerometers in client 102-1),including that the two client devices have physically touched. In someimplementations, the user need not take any action other than bringingthe two devices within the predefined proximity, and hence this issometimes called “zero-click” sharing.

In some implementations, the triggering condition further includessuccessfully establishing a near field communication connection betweenfirst client 102-1 and second client 102-2 (310). Optionally, firstclient 102-1 may need to transmit user authentication information tosuccessfully establish the near field communication connection withsecond client 102-2.

Upon detecting the triggering condition, client 102-1 determines, inaccordance with the stored registration information (214, FIG. 2), thata respective application (e.g., the application running in theforeground of client 102-1) is registered for application state sharing(312), and transmits the application state of the respective applicationto second client 102-2 (314). For ease of explaining method 300, itshall be assumed that the only application for which an applicationstate is to be transmitted to another device is the foregroundapplication, if any, where the foreground application is the applicationrunning in a topmost or foreground application window of first client102-1. However, in some implementations, described in more detail belowwith reference to FIGS. 5A-5C, application state for more than oneapplication is transmitted by first client 102-1 to second client 102-2.

Optionally, the respective application (at client 102-1) is notifiedthat the application state has been transmitted to client 102-2 uponcompletion of the transmission (316). In some embodiments, client 102-1may optionally change the application state of the respectiveapplication in response to the notification (e.g., at the end of thetransmission of the application state) (318). For example, in the casewhere the respective application is a browser application, the browserapplication may terminate after receiving notification that theapplication state has been transmitted. In another example, where therespective application is an email application, after receivingnotification of that the application state has been transmitted toanother client, the draft message or the message being reviewed isclosed, because it is assumed that the user will resume use of the emailapplication at client 102-2. In yet another example, where therespective application is a multimedia player, playback of a video/audioby first client 102-1 is stopped after the multimedia player state issent and notification thereof is provided to the multimedia player.

In some implementations, the respective application is a foregroundapplication, executing in a foreground application window of client102-1 (322, FIG. 3B; 332, FIG. 3C). Typically in client devices such asmobile phones or tablet computers, there is only one foregroundapplication. In some implementations, the application state of therespective application includes at least one of the group consisting of:one or more unsent message drafts, state information for an ongoingtelephone call, a playback position for video content, a playbackposition for audio content, a message account identifier, a messageidentifier for an unsent message draft, a message identifier for acurrently viewed message, a mime type associated with the respectiveapplication (324). A playback position is typically a timestamp and/orframe number. The message identifier can be the message identifier foran unsent message draft, or for a message currently being viewed in theforeground at client 102-1. In some implementations, a copy of theapplication state from the respective application is requested (334)(e.g., application transfer module 108 requests the application statefrom a respective application, and then transfers that application stateto second client 102-2).

Optionally, when the application state of the respective application isstored remotely (e.g., for an online application), a copy of theapplication state from the respective application is requested from arespective server and downloaded to first client 102-1, which thentransfers it to second client 102-1. Alternatively, when the applicationstate of the respective application is stored remotely (e.g., for anonline application), a copy of the application state from the respectiveapplication is requested by second client 102-2 from a respective serverand is downloaded directly second client 102-2.

In some embodiments, at least a portion of the application state istransmitted to second client 102-2 using near field communication (336).Furthermore, in some implementations, at least another portion of theapplication state is transmitted using wireless communication other thannear field communication, such as Bluetooth communication or WiFicommunication (338). In an exemplary implementation, in whichtransmitting the application state would exceed a threshold amount oftime (e.g., 0.5 seconds), a portion of the application state istransferred by NFC and a remaining portion is transferred using anotherwireless communication channel. In yet other implementations, theapplication state is entirely transmitted using a near fieldcommunication connection between the first client device or system andthe second device or system (340).

Method 300 is typically governed by instructions that are stored in anon-transitory computer readable storage medium in a respective client102-1 and that are executed by one or more processors of a respectiveclient device or system 102. Each of the operations shown in FIGS. 3A-3Ctypically corresponds to computer readable instructions which are storedin a computer memory or non-transitory computer readable storage mediumin a respective client 102-1 and which are executed by one or moreprocessors of the respective client 102-1. The non-transitory computerreadable storage medium includes one or more memory devices of client102-1, as described above with respect to FIG. 2. The computer readableinstructions stored on the non-transitory computer readable storagemedium of client 102-1 are typically source code, assembly language codeor object code.

Additionally, it should be noted that details of other processesdescribed herein with respect to methods 400, 500 and 600 (e.g., FIGS.4A-4C, 5A-5C and 6, respectively) are also applicable in an analogousmanner to method 300 described above with respect to FIGS. 3A-3C. Forexample, triggering conditions, and state information transferred mayhave one or more of the characteristics of the various the methodsdescribed herein with reference to methods 400, 500 and 600. Forbrevity, these details are not repeated here.

Attention is now directed to a method 400 of transitioning use of anapplication by a user from one client device (e.g., first client 102-1)to another (e.g., second client 102-2), as illustrated by the flow chartin FIGS. 4A-4C. At first client 102-1 which is under control of arespective user, registration information of applications registered toshare application information with other devices or systems isoptionally retained in memory of client first 102-1 (402). Seeapplication registration information 214, FIG. 2. A first application isactively running on first client 102-1(404). As described above, theapplication state of the actively running application is typicallystored by first client 102-1.

While the first application is running, client 102-1 performs a handoffoperation (406). In some embodiments, the handoff operation is performedby or under the control of application transfer module 108 (FIG. 2). Thehandoff operation begins when client 102-1 detects that it is positionedwithin a predefined proximity of a second device (414). Alternatelystated, the handoff operation begins when client 102-1 detects proximityof the second client. In some implementations, such proximity isdetected by NFC detection module 220 (FIG. 2). As described above,proximity of the second client is typically detected when the secondclient is within 10 cm, 5 cm or 4 cm of first client 102-1 (416).

In some implementations, as part of the handoff operation (406), client102-1 requests from the actively running application (first application)a copy of its current application state (418). Alternatively,application transfer module 108 directly accesses state information forthe actively running application. Client 102-1 transmits applicationinformation (e.g., the aforementioned state information) associated withthe first application to client 102-2 (420).

At second client 102-2, registration information of applicationsregistered to share application information with other devices orsystems is optionally retained (412). Second client 102-2 also detectsproximity of the first client 1021, when the two devices are within apredefined proximity (422). As part of the handoff operation describedabove, second client 102-2 receives the application information fromclient 102-1 (424). In response to receiving application informationfrom first client 102-1, second client 102-2 executes a secondapplication corresponding to the first application with an initial userinterface state corresponding to the first client device user interfacestate (426). In some embodiments, second client 102-2 is under controlof the same user who controls first client 102-1. Unless otherwisestated, however, the handoff operation 406 is performed whether thefirst and second clients are under control of the same user or not.

In some embodiments, the handoff operation occurs when the second deviceor system is physically touched by the first device or system. Forexample, an accelerometer can be used in one or both devices to detectthe touch/bump, which is used to ensure that the handoff is in responseto an intentional act, and thus avoid accidental handoffs.

Referring now to FIG. 4B, as noted above, second client 102-2 receivesapplication state information from first client 102-1(424). Examples ofthe application state information received include the mime type of thefirst application and/or content of the first application. In someembodiments, client 102-2 stores the received application stateinformation and passes the received state information to the secondapplication (430). In some embodiments where a second applicationcorresponding to the mime type does not exist on client 102-2, the userhaving control of second client 102-2 is prompted to download the secondapplication corresponding to the first application (432). Furthermore,second client 102-2 downloads the respective second application (e.g.,from a host server via communications networks 120) in response to userinstruction (434). Second client 102-2 executes a second applicationcorresponding to the first application with an initial user interfacestate corresponding to the first client device user interface state(426). For example, the second application is an application that canprocess content of the same type (e.g., MIME type) as the firstapplication.

In some embodiments, if the second application corresponding to thefirst application is not already executing as a foreground applicationin second client 102-2, in response to receiving application informationfrom first client 102-1, second client 102-2 executes the secondapplication corresponding to the first application as the foregroundapplication (440). In some embodiments where the second application isnot actively running when the handoff operation is performed, secondclient 102-2 automatically starts executing the second applicationwithin a predefined time period (442). For example, the predefined timeperiod is 0.5 seconds such that the starting of the second applicationis not noticeable to the user.

In some implementations, the first application and second applicationare instances of two distinct applications of a same application type(450). In other implementations, the first application and secondapplication are two instances of a same application (452). In yet otherimplementations, the first application and second application areapplications that both handle the same content type(s) (e.g., MIME typeor types), but are optionally different types of applications (e.g., areader/player vs. an editor).

In one example, the first application and second application are bothemail applications (454) (e.g., two distinct email applications, or twoinstances of the same email application). Note, when both applicationsof email applications, it is typically required that both clients 102are under control of the same user or entity to protect the confidentialinformation that may be contained in the email account of the user orentity.

In another example, the first application and second application areboth multimedia players (456). In yet another example, the firstapplication and second application are communication applications foraudio or audio/visual communication (458).

In some embodiments for cases where the first application and secondapplication are both email applications, the first client device userinterface state comprises display of a particular message orconversation thread, and the initial user interface state correspondingto the first client device user interface state comprises display ofsaid particular message or conversation thread. In another example, thefirst client device user interface state comprises display of an unsentdraft message, and the initial user interface state corresponding to thefirst client device user interface state comprises display of saidunsent draft message. In yet another example, the first client deviceuser interface state comprises display of a first list of conversationscorresponding to a user-specified search query, and the initial userinterface state corresponding to the first client device user interfacestate comprises display of a second list of conversations correspondingto the user-specified search query. In some implementations, the firstand second lists are either the same, or one is shorter than the otherwhen one of the client devices has a smaller display than the otherclient device.

In some embodiments for cases where the first application and secondapplication are both multimedia applications, the first client deviceuser interface state comprises playback of a first multimedia item at afirst playback position and the initial user interface statecorresponding to the first client device user interface state comprisesplayback of the first multimedia item at a second playback positioncorresponding to the first playback position. In some embodiments, thesecond playback position has a predefined offset with respect to thefirst playback position. For example, the initial user interface stateat the second client device may be earlier in the playback than thefirst client device user interface state by a predefined offset (e.g.,0.5 to 3.0 seconds earlier), in order to ensure that the handoff doesnot cause the user to miss any content.

In some embodiments, for cases where the first application and secondapplication are both communication applications for audio oraudio/visual communication, the initial user interface state of thesecond client corresponds to a communication connection by the secondclient to a same destination as a communication connection by the firstclient when the handoff operation is performed.

In some embodiments, the application content that is transmitted as partof the application state is selected from the group consisting of a URL,contact information for a respective address book entry, informationidentifying a displayed map, information identifying a displayed map andset of directions for traveling between two locations. For example,second client 102-2, in response to receiving the application state fromthe first client 102-1, uses the mime type included in the receivedapplication state to determine whether the second client has a secondapplication corresponding to the first application. If it is determinedthat it does not have the second application with a matching mime type,second client 102-2 displays a prompt to download a respective secondapplication corresponding to the mime type, downloads the respectivesecond application in response to user instruction, and executes thesecond application.

Referring to FIG. 4C, first client 102-1 not only can hand offapplication information (sometimes herein called state information) fora respective application to another client (e.g., client 102-2), asrepresented by operation 406), but it can also receive applicationinformation from another client during a handoff operation (470). Forexample, after a time after the above described handoff operation 406,the user may want to transfer the state of the same application oranother application back to first client 102-1. Typically, firstapplication 102-1 will have no actively running application, or noapplication running in the foreground, when it receives a handoffoperation. However, in other implementations, various other mechanismsmay be used to determine whether first client 102-1 should acceptapplication information from another client.

The second handoff operation, like the one described above, is typicallyperformed in response to detecting a triggering operation. Triggeringconditions are described above, and therefore that description is notrepeated here. In this second handoff operation, first client 102-1receives from another client device of system application information(e.g., state information) for a third application (472). For example,the received application information includes a mime type andapplication content and/or state information. Such information isdescribed above, and thus is not repeated here. Typically, the receivedapplication information is stored by first client 102-1 and passed to arespective application (e.g., a fourth application) corresponding to thethird application (474). In some implementations, the respectiveapplication to be used is determined in accordance with the mime typespecified in the received application information. The respectiveapplication (e.g., fourth application) corresponding to the thirdapplication is executed by the first client device, with an initial userinterface corresponding to the user interface at the other client deviceor system from which the application information was received (476).

Method 400 is typically be governed by instructions that are stored in anon-transitory computer readable storage medium in a respective client102-1 and that are executed by one or more processors of a respectiveclient device or system 102. Each of the operations shown in FIGS. 4A-4Ctypically corresponds to computer readable instructions which are storedin a computer memory or non-transitory computer readable storage mediumin a respective client 102-1 and which are executed by one or moreprocessors of the respective client 102-1. The non-transitory computerreadable storage medium includes one or more memory devices of client102-1, as described above with respect to FIG. 2. The computer readableinstructions stored on the non-transitory computer readable storagemedium of client 102-1 are typically source code, assembly language codeor object code.

Additionally, it should be noted that details of other processesdescribed herein with respect to methods 300, 500 and 600 (e.g., FIGS.3A-3C, 5A-5C and 6, respectively) are also applicable in an analogousmanner to method 400 described above with respect to FIGS. 4A-4C. Forexample, triggering conditions, and state information transferred mayhave one or more of the characteristics of the various the methodsdescribed herein with reference to methods 300, 500 and 600. Forbrevity, these details are not repeated here.

FIGS. 5A-5C include a flow chart illustrating a method 500 of operationof a client device or system (hereinafter called a client for ease forreference) according to some embodiments. Method 500 is performed by aclient device or system, such as first client 102-1 described above withreference to FIGS. 1 and 2. First client 102-1 executes a plurality ofactively running applications with one or multiple checkpoints, eachcheckpoint identifying an execution breakpoint at which the respectiveapplication can be suspended and subsequently resumed (502). Theapplication state of the respective application for each respectiveapplication of the plurality of actively running applicationscorresponding to a checkpoint of the respective application isdynamically stored either in memory of the client or in memory of aserver at a remote location from the client (504). A transfer triggeringcondition for transferring application state of the actively runningapplications to another device client (e.g., from first client 102-1 tosecond client 102-2, FIG. 1) is detected (506). Optionally, client102-optionally waits for the plurality of actively running applicationsto enter their respective checkpoints and suspends execution of theplurality of actively running applications (508, 511). Alternatively, insome implementations, upon detecting the triggering condition, firstclient 102-1 suspends a respective actively running application of theplurality of actively running applications when the respective activelyrunning application reaches a checkpoint of the respective activelyrunning application (509).

The stored application state of the plurality of actively runningapplications is transmitted to client 102-2 (512). In some embodiments,each of the actively running applications is notified that theapplication state has been transmitted to the second client device(514).

Referring to FIG. 5B, in some embodiments, detecting the transfertriggering condition (506) includes detecting presence of another clientdevice or system (e.g., second client 102-2) within a predefinedproximity of first client 102-1 (308). Furthermore, as described above,in some embodiments, the predefined proximity is the proximity requiredto successfully establish an NFC channel (also called an NFC connection)between two devices, or to successfully conduct NFC communications(507). In some implementations, detecting the transfer triggeringcondition includes establishing an NFC channel (310). In someembodiments, the transfer triggering condition includes an instructionby a user (e.g., pressing a button or object on a touch sensitivedisplay) of the first client device or system (526). However, in manyimplementations, no user action other than bringing the two devicesclose to each other is required.

Referring to FIG. 5C, in some embodiments, first client 102-1 startstransmitting the stored application state of the plurality of activelyrunning applications only after detecting the suspension of theplurality of active applications (528). Alternatively, in someembodiments, first client 102-1 transmits the stored application stateof an application to the second device or system after detecting thesuspension of the respective active application without waiting for thesuspension of the other still actively running applications (530). Insome embodiments (not shown in FIGS. 5A-5C), first client 102-1transmits the stored application state of the plurality of activelyrunning applications after a predefined number of applications have beensuspended.

In some embodiments, to minimize the delay of transferring theapplication state from first client 102-1 to second client 102-2, thetransfer triggering condition comprises detecting the NFC field of thesecond device without forming a NFC connection. In some embodiments,first client 102-1 establishes a NFC connection with second client 102-2either after having suspended the plurality of actively runningapplications, or while in the process of suspending execution of theplurality of actively running applications.

In some implementations, first client 102-1 transmits userauthentication information as part of the application state transmittedto second client 102-2 (532).

As described above, in some embodiments, at least a portion of theapplication state is transmitted to second client 102-2 using near fieldcommunication (336). Furthermore, in some implementations, at leastanother portion of the application state is transmitted using wirelesscommunication other than near field communication, such as Bluetoothcommunication or WiFi communication (338). In yet other implementations,the application state is entirely transmitted using a near fieldcommunication connection between the first client device or system andthe second device or system (340).

Method 500 is typically be governed by instructions that are stored in anon-transitory computer readable storage medium in a respective client102-1 and that are executed by one or more processors of a respectiveclient device or system 102. Each of the operations shown in FIGS. 5A-5Ctypically corresponds to computer readable instructions which are storedin a computer memory or non-transitory computer readable storage mediumin a respective client 102-1 and which are executed by one or moreprocessors of the respective client 102-1. The non-transitory computerreadable storage medium includes one or more memory devices of client102-1, as described above with respect to FIG. 2. The computer readableinstructions stored on the non-transitory computer readable storagemedium of client 102-1 are typically source code, assembly language codeor object code.

Additionally, it should be noted that details of other processesdescribed herein with respect to methods 300, 400 and 600 (e.g., FIGS.3A-3C, 4A-4C and 6, respectively) are also applicable in an analogousmanner to method 500 described above with respect to FIGS. 5A-5C. Forexample, triggering conditions, and state information transferred mayhave one or more of the characteristics of the various the methodsdescribed herein with reference to methods 300, 400 and 600. Forbrevity, these details are not repeated here.

FIG. 6 includes a flow chart illustrating a method 600 of operation of aclient device or system according to some embodiments. Method 600 isperformed by a client device or system, such as client device or system102-1 described above with reference to FIGS. 1 and 2. Client 102-1executes an actively running application having one or more checkpoints,each checkpoint identifying an execution breakpoint at which theactively running application can be suspended and subsequently resumed(602). The application state of the respective actively runningapplication corresponding to a checkpoint of the respective applicationis dynamically stored either in memory of the client or in memory of aserver at a remote location from the client (604). A transfer triggeringcondition for transferring application state of the respectiveapplication to another device client (e.g., from client 102-1 to client102-2, FIG. 1) is detected (606). In some embodiments, the transfertriggering condition includes presence of the second client device orsystem within a predefined proximity of the first client device orsystem (306, see also above description with reference to FIG. 5B).Furthermore, in some embodiments, the predefined proximity is apredefined proximity for near field communication (308, FIG. 5B,described above with reference to FIG. 5B). In some embodiments, thetransfer triggering condition includes an instruction by a user (e.g.,pressing a button or object on a touch sensitive display) of the firstclient device or system (526, described above with reference to FIG.5B).

Method 600 is typically be governed by instructions that are stored in anon-transitory computer readable storage medium in a respective client102-1 and that are executed by one or more processors of a respectiveclient device or system 102. Each of the operations shown in FIG. 6typically corresponds to computer readable instructions which are storedin a computer memory or non-transitory computer readable storage mediumin a respective client 102-1 and which are executed by one or moreprocessors of the respective client 102-1. The non-transitory computerreadable storage medium includes one or more memory devices of client102-1, as described above with respect to FIG. 2. The computer readableinstructions stored on the non-transitory computer readable storagemedium of client 102-1 are typically source code, assembly language codeor object code.

Additionally, it should be noted that details of other processesdescribed herein with respect to methods 300, 400 and 500 (e.g., FIGS.3A-3C, 4A-4C and 5A-5C, respectively) are also applicable in ananalogous manner to method 600 described above with respect to FIG. 6.For example, triggering conditions, and state information transferredmay have one or more of the characteristics of the various the methodsdescribed herein with reference to methods 300, 400 and 500. Forbrevity, these details are not repeated here.

The foregoing description, for purpose of explanation, has beendescribed with reference to specific embodiments. However, theillustrative discussions above are not intended to be exhaustive or tolimit the invention to the precise forms disclosed. Many modificationsand variations are possible in view of the above teachings. Theembodiments were chosen and described in order to best explain theprinciples of the invention and its practical applications, to therebyenable others skilled in the art to best utilize the invention andvarious embodiments with various modifications as are suited to theparticular use contemplated.

1. A method, performed by a first client device or system having one ormore processors and memory storing one or more programs for execution bythe one or more processors, the method comprising: retaining in thememory of the first client device of system registration information fora respective application indicating the respective application isregistered for sharing application state with other client devices orsystems; detecting a transfer triggering condition, the transfertriggering condition comprising presence of a second client device orsystem within a predefined proximity of the first client device orsystem, wherein the predefined proximity is a predefined proximity fornear field communication; and upon detecting the triggering condition,determining in accordance with the stored registration information thatthe respective application is registered for application state sharing,and transmitting an application state of the respective application tothe second client device or system.
 2. The method of claim 1, whereintransmitting the application state further comprises requesting a copyof the application state from the respective application.
 3. The methodof claim 1, wherein transmitting the application state comprisestransmitting at least a portion of the application state using nearfield communication.
 4. The method of claim 3, wherein transmitting theapplication state further comprises transmitting at least anotherportion of the application state using wireless communication other thannear field communication.
 5. The method of claim 1, wherein transmittingthe application state comprises transmitting the application state usinga near field communication connection between the first client device orsystem and the second client device or system.
 6. The method of claim 1,wherein detecting the transfer triggering condition further comprisesestablishing a near field communication connection between the firstclient device or system and the second client device or system.
 7. Themethod of claim 1, wherein the respective application is a foregroundapplication of the first client device.
 8. The method of claim 1,wherein the application state of the respective application includes atleast one of the group consisting of: one or more unsent message drafts,state information for an ongoing telephone call, a playback position forvideo content, a playback position for audio content, a message accountidentifier, a message identifier for an unsent message draft, a messageidentifier for a currently viewed message, and a mime type associatedwith the respective application.
 9. The method of claim 1, furthercomprising notifying the respective application that the applicationstate has been transmitted to the second client device or system. 10.The method of claim 9, further comprising changing the application stateof the respective application in response to the notification.
 11. Anon-transitory computer readable storage medium storing one or moreprograms for execution by one or more processors of a client device orsystem, the one or more programs comprising instructions to: retain inmemory of the first client device or system registration information fora respective application indicating the respective application isregistered for sharing application state with other client devices orsystems; detect a transfer triggering condition, the transfer triggeringcondition comprising presence of a second client device or system withina predefined proximity of the first client device or system, wherein thepredefined proximity is a predefined proximity for near fieldcommunication; and upon detecting the triggering condition, determine inaccordance with the stored registration information that the respectiveapplication is registered for application state sharing, and transmit anapplication state of the respective application to the second clientdevice or system.
 12. The computer readable storage medium of claim 11,wherein the instructions to transmit the application state furthercomprise instructions to request a copy of the application state fromthe respective application.
 13. The computer readable storage medium ofclaim 11, wherein the instructions to transmit the application statecomprise instructions to transmit at least a portion of the applicationstate using near field communication.
 14. The computer readable storagemedium of claim 13, wherein the instructions to transmit the applicationstate further comprise instructions to transmit at least another portionof the application state using wireless communication other than nearfield communication.
 15. The computer readable storage medium of claim11, wherein the instructions to transmit the application state furthercomprises instructions to transmit the application state using a nearfield communication connection between the first client device or systemand the second client device or system.
 16. The computer readablestorage medium of claim 11, wherein the instructions to detect thetransfer triggering condition further comprise instructions to establisha near field communication connection between the first client device orsystem and the second client device or system.
 17. The computer readablestorage medium of claim 11, wherein the respective application is aforeground application of the first client device.
 18. The computerreadable storage medium of claim 11, wherein the application state ofthe respective application includes at least one of the group consistingof: one or more unsent message drafts, state information for an ongoingtelephone call, a playback position for video content, a playbackposition for audio content, a message account identifier, a messageidentifier for an unsent message draft, a message identifier for acurrently viewed message, and a mime type associated with the respectiveapplication.
 19. The computer readable storage medium of claim 11,wherein the one or more programs further comprise instructions to notifythe respective application that the application state has beentransmitted to the second client device or system.
 20. The computerreadable storage medium of claim 19, wherein the one or more programsfurther comprise instructions to change the application state of therespective application in response to the notification.
 21. A clientdevice or system, comprising: one or more communication interfaces,including a near field communication transceiver; one or moreprocessors; and memory storing one or more programs for execution by theone or more processors, the one or more programs comprising instructionsto: retain in memory of the client device or system registrationinformation for a respective application indicating the respectiveapplication is registered for sharing application state with otherclient devices or systems; detect a transfer triggering condition, thetransfer triggering condition comprising presence of a second clientdevice or system within a predefined proximity of the first clientdevice or system, wherein the predefined proximity is a predefinedproximity for near field communication; and upon detecting thetriggering condition, determine in accordance with the storedregistration information that the respective application is registeredfor application state sharing, and transmitting an application state ofthe respective application to the second client device or system. 22.The client device or system of claim 21, wherein the instructions totransmit the application state further comprise instructions to requesta copy of the application state from the respective application.
 23. Theclient device or system of claim 21, wherein the instructions totransmit the application state comprise instructions to transmit atleast a portion of the application state using near field communication.24. The client device or system of claim 23, wherein the instructions totransmit the application state further comprise instructions to transmitat least another portion of the application state using wirelesscommunication other than near field communication.
 25. The client deviceor system of claim 21, wherein the instructions to transmit theapplication state comprises instructions to transmit the applicationstate using a near field communication connection between the firstclient device or system and the second client device or system.
 26. Theclient device or system of claim 21, wherein the instructions to detectthe transfer triggering condition further comprise instructions toestablish a near field communication connection between the first clientdevice or system and the second client device or system.
 27. The clientdevice or system of claim 21, wherein the respective application is aforeground application of the first client device.
 28. The client deviceor system of claim 21, wherein the application state of the respectiveapplication includes at least one of the group consisting of: one ormore unsent message drafts, state information for an ongoing telephonecall, a playback position for video content, a playback position foraudio content, a message account identifier, a message identifier for anunsent message draft, a message identifier for a currently viewedmessage, and a mime type associated with the respective application. 29.The client device or system of claim 21, wherein the one or moreprograms further comprise instructions to notify the respectiveapplication that the application state has been transmitted to thesecond client device or system.
 30. The client device or system of claim29, wherein the one or more programs further comprise instructions tochange the application state of the respective application in responseto the notification.